I'm trying to decide which way to go, keep the 4xshaman or go with the 4x Priests (shadow)

The Priests are undead and the fear/anti-fear seems nice for pvp but is this just a pipe dream? Is fear bombing less of a concern then like dealing with a rogue?

Please, ply me with your wisdom as to which is better for a PvP server from your experience.

1Pal + 4 Shaman?
1Pal + 4 Priests?